To simplify $\sqrt{64}$ into its simplest radical form, we need to find the square root of 64.

Since $64 = 8^2$, the square root of 64 is $8$.

Thus, $\sqrt{64} = 8$.

Would you like further clarification or details? Here are some follow-up questions to deepen your understanding:

1. What is a radical expression and how can it be simplified?
2. Can all square roots be simplified to whole numbers?
3. How do we handle square roots of numbers that are not perfect squares?
4. What is the difference between simplest radical form and decimal approximation?
5. Can you provide more examples of simplifying square roots?

Tip: Always check if the number under the square root is a perfect square to simplify it directly.